what do this do ? and how do it works

 

Use the SEARCH function. All questions you may have have already been covered on this Forum.
Also, you've been given the FSM link to your car. That will also answer your questions.

 

Download the FSM from the link in my sig and go through the trouble shooting section.
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whats its actually called is the vacuume control solenoid valve. it'll be the solenoid that the green connector on your rats nest is clipped into. what it does is it'll cut the vacuume to your distributor when you are decelerating